Didecyldimethylammonium chloride (Ref: P0151)

Didecyldimethylammonium chloride (Ref: P0151)	Last updated: 26/05/2025
(Also known as: DDAC)

SUMMARY

Didecyldimethylammonium chloride is mainly used as a biocide. It is highly soluble in water and has a low volatility. It may be environmentally persistent depending on local conditions. It is highly toxic to aquatic invertebrates and moderately toxic to fish. Didecyldimethylammonium chloride also has a moderate oral mammalian toxicity and is an irritant.

Data alerts

The following alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement.

Environmental fate	Ecotoxicity	Human health
Environmental fate Low alert: Drainflow: Non-mobile Warning: Significant data are missing	Ecotoxicity High alert: Daphnia acute ecotoxicity: High	Human health Moderate alert: Mammals acute toxicity: Moderate; Reproduction/development effects; Neurotoxicant

GENERAL INFORMATION

Description

An antiseptic and disinfectant that is mainly used as a biocide. It shows a broad-spectrum of activity against both gram-positive and gram-negative bacteria and also fungicidal activity.

Example pests controlled

Phytopathogenic fungi, bacteria and algae.

Example applications

Citrus; Hard Surfaces; Horticultutral & medical equipment; Glasshouse structures; Linen; Non-agricultural areas such as pavements, walkways

Efficacy & activity

Availability status

Current

Introduction & key dates

1962, first registered as antimicrobial agent, USA

GB regulatory status

GB COPR regulatory status

Not approved

Date COPR inclusion expires

Expired

GB LERAP status

No UK approval for use as a plant protection agent

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Netherlands

Date EC 1107/2009 inclusion expires

Expired

EU Candidate for substitution (CfS)

Not applicable

Listed in EU database

Yes

Approved for use (✓) under EC 1107/2009 in the following EU Member States

ATAustria	BEBelgium	BGBulgaria	CYCyprus	CZCzech Republic	DEGermany	DKDenmark	EEEstonia	ELGreece

ESSpain	FIFinland	FRFrance	HRCroatia	HUHungary	IEIreland	ITItaly	LTLithuania	LULuxembourg

LVLatvia	MTMalta	NLNetherlands	PLPoland	PTPortugal	RORomania	SESweden	SISlovenia	SKSlovakia

Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries

ISIceland	NONorway

Additional information

Also used in

Canada

Chemical structure

Isomerism

None

Chemical formula

C₂₂H₄₈ClN

Canonical SMILES

CCCCCCCCCC[N+](C)(C)CCCCCCCCCC.[Cl-]

Isomeric SMILES

International Chemical Identifier key (InChIKey)

RUPBZQFQVRMKDG-UHFFFAOYSA-M

International Chemical Identifier (InChI)

InChI=1S/C22H48N.ClH/c1-5-7-9-11-13-15-17-19-21-23(3,4)22-20-18-16-14-12-10-8-6-2;/h5-22H2,1-4H3;1H/q+1;/p-1

2D structure diagram/image available?

Yes

General status

Pesticide type

Fungicide; Herbicide; Algicide; Other substance

Other bioactivity & uses

Cationic surfactant; Antiseptic; Bactericide; Disinfectant

Substance groups

Quaternary ammonium compound

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Broad-spectrum, non-systemic. It causes the disruption of intermolecular interactions and the dissociation of lipid bilayers.

CAS RN

7173-51-5

EC number

230-525-2

CIPAC number

859

US EPA chemical code

069149

PubChem CID

23558

CLP index number

612-131-00-6

Molecular mass

362.08

PIN (Preferred Identification Name)

IUPAC name

CAS name

N-decyl-N,N-dimethyl-1-decanaminium chloride

Other status information

Chemical subject to PIC regulations

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Not known

Herbicide Resistance Class (WSSA MoA class)

Not known

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

Not known

Examples of recorded resistance

Physical state

Off-white sticky powder

Formulations

Property

Value

Example manufacturers & suppliers of products using this active now or historically

Example products using this active

M and ENNO-TER forte
Timbercote
Bardac 2270

Formulation and application details

Usually supplied as a soluble liquid that is diluted prior to use.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

500000

High

Solubility - In organic solvents at 20 °C (mg l⁻¹)

600000

Acetone

600000

Methanol

250000

n-Octanol

Melting point (°C)

197

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

280

Flashpoint (°C)

21-55

Octanol-water partition coefficient at pH 7, 20 °C

1.00 X 10⁰¹

Calculated

Log P

1.0

Low

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

0.95

Dissociation constant pKa) at 25 °C

Completely dissociated

Vapour pressure at 20 °C (mPa)

5.9 X 10^-03

Low volatility

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

4.3 X 10^-09

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

Surface tension (mN m⁻¹)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Stable

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

Stable

Note

Stable pH 5 to pH 9 at 25 °C

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Sediment phase only DT₅₀ (days)

Air degradation

As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.

Decay in stored produce DT₅₀

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

30851

Non-mobile

K_foc (mL g⁻¹)

1470000

¹/_n

1.02

Notes and range

EU dossier K_f range 8179-32791 mL g⁻¹, K_foc range 908757-1599564 mL g⁻¹,¹/_n range 0.96-1.03

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate

Value

Cannot be calculated

Note

Potential for particle bound transport index

Potential for loss via drain flow

Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk

4.3

Calculated using the Atkinson method. Assumed 9.7E+05 OH/cm³, 12 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

150

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

Birds - Short term dietary (LC₅₀/LD₅₀)

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

> 1000

Eisenia foetida

Low

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Honeybees (Apis spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Chronic

Notes

Bumblebees (Bombus spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Mason bees (Osmia spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Other bee species (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other bee species (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

1.16

Oncorhynchus mykiss

Moderate

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

0.032

Danio rerio

Moderate

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

0.094

Daphnia magna

High

Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

0.01

Daphnia magna

Moderate

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

> 0.069

Ceriodaphnia dubia LC₅₀

High

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic plants (free-floating, growth) - Acute 7 day EC₅₀, biomass (mg l⁻¹)

Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

150

Rat

Moderate

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

4000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

None allocated

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

None allocated

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

None allocated

Dermal penetration studies (%)

100

default

Dangerous Substances Directive 76/464

Exposure Routes

Public

No consumer exposure due to pattern of use

Occupational

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

GB MRL expected to deviate from the EU MRL in mid-2023

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

May cause serious eye damage

Handling issues

Property

Value and interpretation

General

Corrosive
Combustible
IMDG Transport Hazard Class 8
Will emit hazardous combustion gases in the event of fire

CLP classification 2013

Health: H302, H314, H319, H335
Handling: H227
Environment: H400

WHO Classification

Not listed (Not listed)

UN Number

UN2923

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

Chemically stable under standard ambient conditions

TRANSLATIONS

Language

Name

English

didecyldimethylammonium chloride

French

chlorure de didécyldiméthylammonium

German

Didecyldimethylammoniumchlorid

Danish

Italian

Spanish

cloruro de didecildimetilamonio

Greek

Polish

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	26/05/2025
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242